A combo of the two most despicable political parties (according to the U.S.) Communists and Nazis. As the mixture of these two beliefs would basically be a moderate, the word is used solely as an insult.

After the realization that communism and fascism are functionally equivalent ideologies, it was a concern that some people who consider themselves communists and/or nazis may only be insulted by association with the crimes of one or the other group, rather than both as they justly deserve.

As such, the portmanteau 'Communazi' was invented to amend this gaping flaw in the English language.

After killing 62 million innocent people to Mao's mere 49 million and Hitler's frankly pitiful 48 million, Stalin conclusively won the Communazi Olympics.